Introduce exception object and remove some uses of MaybeObject::IsFailure().

src/heap.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2543 matching lines @@
     ALLOCATE_VARSIZE_MAP(FIXED_ARRAY_TYPE, scope_info)
     ALLOCATE_MAP(HEAP_NUMBER_TYPE, HeapNumber::kSize, heap_number)
     ALLOCATE_MAP(SYMBOL_TYPE, Symbol::kSize, symbol)
     ALLOCATE_MAP(FOREIGN_TYPE, Foreign::kSize, foreign)
 
     ALLOCATE_MAP(ODDBALL_TYPE, Oddball::kSize, the_hole);
     ALLOCATE_MAP(ODDBALL_TYPE, Oddball::kSize, boolean);
     ALLOCATE_MAP(ODDBALL_TYPE, Oddball::kSize, uninitialized);
     ALLOCATE_MAP(ODDBALL_TYPE, Oddball::kSize, arguments_marker);
     ALLOCATE_MAP(ODDBALL_TYPE, Oddball::kSize, no_interceptor_result_sentinel);
+    ALLOCATE_MAP(ODDBALL_TYPE, Oddball::kSize, exception);
     ALLOCATE_MAP(ODDBALL_TYPE, Oddball::kSize, termination_exception);
 
     for (unsigned i = 0; i < ARRAY_SIZE(string_type_table); i++) {
       const StringTypeTable& entry = string_type_table[i];
       { MaybeObject* maybe_obj = AllocateMap(entry.type, entry.size);
         if (!maybe_obj->ToObject(&obj)) return false;
       }
       roots_[entry.index] = Map::cast(obj);
     }
 
@@ skipping 284 matching lines @@
                            "no_interceptor_result_sentinel",
                            handle(Smi::FromInt(-2), isolate()),
                            Oddball::kOther));
 
   set_termination_exception(
       *factory->NewOddball(factory->termination_exception_map(),
                            "termination_exception",
                            handle(Smi::FromInt(-3), isolate()),
                            Oddball::kOther));
 
+  set_exception(
+      *factory->NewOddball(factory->exception_map(),
+                           "exception",
+                           handle(Smi::FromInt(-5), isolate()),
+                           Oddball::kException));
+
   for (unsigned i = 0; i < ARRAY_SIZE(constant_string_table); i++) {
     Handle<String> str =
         factory->InternalizeUtf8String(constant_string_table[i].contents);
     roots_[constant_string_table[i].index] = *str;
   }
 
   Object* obj;
 
   // Allocate the hidden string which is used to identify the hidden properties
   // in JSObjects. The hash code has a special value so that it will not match
@@ skipping 3836 matching lines @@
       static_cast<int>(object_sizes_last_time_[index]));
   CODE_AGE_LIST_COMPLETE(ADJUST_LAST_TIME_OBJECT_COUNT)
 #undef ADJUST_LAST_TIME_OBJECT_COUNT
 
   OS::MemCopy(object_counts_last_time_, object_counts_, sizeof(object_counts_));
   OS::MemCopy(object_sizes_last_time_, object_sizes_, sizeof(object_sizes_));
   ClearObjectStats();
 }
 
 } }  // namespace v8::internal